DE3885171T2 - Benzoyl acetanilide couplers and photographic materials and processes containing the same. - Google Patents

Description

This invention relates to photographic yellow dye-forming benzoylacetanilide couplers which release a photographically useful group upon coupling with oxidized color developing agent, and to photographic materials containing such couplers.

It is known that desirable photographic effects can be obtained in the field of color photography if the couplers involved in image formation release a photographically usable group when coupled with oxidized color developing agent. Examples of such couplers are those which contain the residue of a development inhibitor (DIR coupler) or the residue of a masking dye. Such couplers correspond to the form:

COUPLER - PUG

wherein PUG is the residue of a photographically useful group which is attached to the coupler in its coupling position and which is consequently released upon coupling.

U.S. Patent 4,248,962 describes couplers of the formula:

COUPLER-TIME- PUG

in which the TIME-PUG residue is released upon coupling, after which, after a short delay, PUG is released from TIME (a timing group). Such couplers which release a development inhibitor have been referred to as anchiometric development inhibitor releasing couplers (DIAR couplers). This means that the release of the photographically useful group is delayed, resulting in desirable photographic effects. The description applies generally to all classes of couplers. Coupler No. 28 (column 29) corresponds to the formula:

and couplers No. 29 and No. 30 are similar, all of these couplers containing a development inhibitor moiety attached via a TIME group in the coupling position.

German OLS 3,518,231 A1 describes a pivaloylacetanilide with a TIME-PUG group as described in U.S. patent 4,248,962.

Japanese Patent Publication JP-A-58205150 describes ballasted alkoxybenzoylacetanilide couplers having a development inhibitor moiety attached via a timing group. The ballast group on the anilide moiety is a -CONH-aryl group, but its electron withdrawing ability is moderate. In the present invention, ballast groups are used which are much stronger electron withdrawing groups and which result in increased activity, which in turn leads to a faster release of the timing inhibitor moiety, which enables it to diffuse further during development, resulting in a greater effect on remote receiving layers.

A class of benzoylacetanilide couplers has been discovered that are more effective than the prior art pivaloylacetanilide DIAR couplers.

The present invention provides a color photographic element comprising a support having thereon at least one silver halide photographic emulsion layer and a non-diffusing photographic color coupler of the following formula:

where TIME is a group of the following formula:

R¹ is an alkyl group, R² and R³ each represent hydrogen or an electron-withdrawing group of the formula:

-SO₂NH-R⁶ -NO₂

-SO-R6 -CN

-SO₂-R⁶-CF₃

-CO-R&sup6; -OP(OR6)2

-CO₂R⁶ or -OSO₂R⁶

where at least one of them does not represent hydrogen,

R⁴ represents a hydrogen atom or one or more substituents,

R⁵ is an alkyl group having 1-4 carbon atoms or a hydroxyphenyl group,

R6 is an alkyl group,

R⁷ is a -NO₂, -NHSO₂CH₃, -NHCOCH₃, -SO₂NHCH₃, -SO₂CH₃ or a -CN group,

R⁸ represents hydrogen, chlorine or a methyl group,

R⁹ stands for hydrogen or has the meaning of R⁹,

PUG is the residue of a photographically usable compound, and

n is equal to 0 or 1.

Preferably, R6 is an alkyl group having 1-20 carbon atoms. Examples of alkyl groups that R1 can represent are methyl, ethyl, n-butyl, t-butyl, hexyl, dodecyl and hexadecyl groups.

It should be noted that in order to ensure that the couplers in the element are non-diffusing, they comprise a group or groups of suitable size and configuration. Such groups are generally referred to as ballast groups and can be present in the groups R¹, R² and/or R³.

The group PUG can be, for example, a residue of a development inhibitor, a dye, a coupler or a development accelerator. Details of such groups can be found in U.S. Patents 3,227,554; 3,701,783; 3,615,506; 3,617,291; 3,379,529; 3,620,746; 3,384,657; 3,733,201; 4,248,962 and 4,409,323. Specific development inhibitor residues include mercaptotetrazoles or, less desirably, benzotriazoles and benzodiazoles. Examples of inhibitor residues include the following:

where A is N or CR,

Q stands for O, S or NR, and

R is a hydrogen atom or an alkyl group.

In the following Table 1, two specific examples of couplers according to the present invention are given together with two comparative couplers G and H. Table 1 CO-INHIBITOR Compound INHIBITOR

The dye-forming couplers of this invention can be used in the manner and for the purposes in which corresponding dye-forming couplers have been used heretofore in the photographic field. They can be incorporated into photographic materials, for example by dissolving them in a high boiling and/or low boiling solvent and forming a dispersion in gelatin.

Typically, the couplers are incorporated into photographic elements in such a way that they are associated with a silver halide emulsion. As used herein, the term "associated with" means that the coupler can be located in the silver halide emulsion layer itself or in a position adjacent thereto from which it can enter into reactive association with the silver halide development products during the development process.

Often the present DIAR couplers are associated with the yellow dye image-forming layers so that any yellow image formed therefrom is part of the yellow image. However, this is not essential and in the case where a small amount of yellow can be tolerated, the coupler may be associated with other layers, e.g. the magenta image dye-forming layers.

The photographic elements may be single color elements or multicolor elements. For example, in the case of a multicolor element, yellow dye-forming couplers are usually associated with a blue-sensitive emulsion, although they may also be associated with or associated with an emulsion sensitized to another region of the spectrum, or they may be associated with or associated with a panchromatically sensitized emulsion, an orthochromatically sensitized emulsion, or a non-sensitized emulsion. Multicolor elements contain dye image-forming units which sensitized to each of the three primary regions of the spectrum. Each unit may be comprised of a single emulsion layer or of multiple emulsion layers sensitized to a particular region of the spectrum. The layers of the element, including the layers of the imaging units, may be arranged in various orders, as is well known.

A typical multicolor photographic element comprises a support having thereon a yellow dye image-forming unit comprising at least one blue-sensitive silver halide emulsion layer having associated therewith at least one yellow dye-forming coupler, and further comprising thereon magenta and cyan dye image-forming units comprising at least one green- or red-sensitive silver halide emulsion layer having associated therewith at least one magenta or cyan dye-forming coupler, respectively. The elements may comprise additional layers, such as filter layers.

In the following discussion of suitable materials for use in the emulsions and elements of this invention, reference is made to Research Disclosure, December 1978, No. 17643, published by Industrial Opportunities Ltd., The Old Harbourmaster's, 8 North Street, Emsworth, Hants P010 7DD, United Kingdom. This publication is hereinafter referred to as "Research Disclosure".

The silver halide emulsions used in the elements of this invention can be either negative working emulsions or positive working emulsions. Suitable emulsions and their preparation are described in Research Disclosure, Sections I and II and the publications cited therein. Suitable binders and vehicles for the emulsion layers and other layers of the elements of this invention are described in Research Disclosure, Section IX and the publications cited therein.

In addition to the couplers of this invention, the materials of the invention may contain additional couplers as described in Research Disclosure, Section VII, Paragraphs D, E, F and G and the publications cited therein. The couplers of this invention and any other additional couplers may be incorporated into the elements and emulsions as described in Research Disclosure, Section VII, Paragraph C and the publications cited therein.

The photographic materials of this invention or individual layers thereof may contain optical brighteners (see Research Disclosure, Section V), antifoggants and stabilizers (see Research Disclosure, Section VI), antistaining agents and image dye stabilizers (see Research Disclosure, Section VII, paragraphs I and J), light absorbing and light scattering materials (see Research Disclosure, Section VIII), hardeners (see Research Disclosure, Section XI), plasticizers and lubricants (see Research Disclosure, Section XII), antistatic agents (see Research Disclosure, Section XIII), matting agents (see Research Disclosure, Section XVI) and development modifiers (see Research Disclosure, Section XXI).

The photographic elements can be prepared by coating a variety of supports as described in Research Disclosure, Section XVII and the references cited therein.

The photographic elements can be exposed to actinic radiation, typically in the visible region of the spectrum, to form a latent image as described in Research Disclosure, Section XVIII and processed to form a visible dye image as described in Research Disclosure, Section XIX. Processing to form a visible Dye image formation includes the step of contacting the element with a color developing agent to reduce developable silver halide and oxidize the color developing agent. Oxidized color developing agent then reacts with the coupler to form a dye.

Preferred color developing agents are p-phenylenediamines. Particularly advantageous are 4-amino-3-methyl-N,N-diethylaniline hydrochloride; 4-amino-3-methyl-N-ethyl-N-β-(methanesulfonamido)ethylaniline sulfate hydrate; 4-amino-3-methyl-N-ethyl-N-β-hydroxyethylaniline sulfate; 4-amino-3-β-(methanesulfonamido)ethyl-N,N- diethylaniline hydrochloride and 4-amino-N-ethyl-N-(2-methoxyethyl)-m-toluidine di-p-toluenesulfonate.

When negative-working silver halide emulsions are used, this step results in a negative image. To obtain a positive (or reversal) image, this step can be preceded by development with a non-chromogenic developer to develop exposed silver halide but not to form the dye, and then the element is uniformly fogged to render unexposed silver halide developable. Alternatively, a direct-positive emulsion can be used to obtain a positive image.

Development is followed by the usual steps of bleaching, fixing or bleach-fixing to remove silver and silver halide, washing and drying.

The couplers of the present invention can be prepared according to the following scheme: Kupp Kupp Note: PMT = 1-phenyl-5-thiotetrazole.

The first step can be carried out in dimethylformamide, whereas the second step can be carried out in an alkaline dimethyl sulfoxide solution. The final step can be carried out in dry ethyl acetate, using 1-2 equivalents of carbonyldi-(1-phenyl-5-thiotetrazole).

The following examples are intended to further illustrate the invention.

example 1

Compound 2 of Table 1 was prepared as follows:

(Me here means CH₃-)

(Et here means C₂H₅-)

Connection (ii)

The two-equivalent coupler (i) (25 g, 39 mmol) was taken up in dry dimethylformamide (250 cm³) and N-ethyl-N-(2-hydroxy-5-nitrophenylmethyl)trifluoroacetamide (46.5 g, 125 mmol) was added. The solution was purged with nitrogen for 30 minutes, triethylamine (16.5 cm³, 117 mmol) was added and the mixture was heated at 50° for 1.5 hours. Thin layer chromatography (tlc) analysis was performed to show that all of the starting coupler had reacted.

The reaction mixture was poured into water (3 l) plus concentrated hydrochloric acid (150 cm³), after which the whole with ethyl acetate (3 x 500 cm³). This organic extract was washed successively with 500 cm³ portions of brine, ice-cold 1M sodium hydroxide solution (3 x), brine and 3M hydrochloric acid (3 x). The organic phase was dried over magnesium sulfate and concentrated to give a glassy solid which was recrystallized from cyclohexane (330 cm³) to give the product as a brittle solid, 30 g, 86%.

Connection (iii)

A sodium hydroxide solution (3M, 12 cm3) was added to dimethyl sulfoxide (12 cm3) and the resulting solution was cooled to room temperature before being added to a solution of (ii) (6 g, 6.7 mmol) in dimethyl sulfoxide (120 cm3) stirred at room temperature under a nitrogen atmosphere. After stirring for 10 minutes, thin layer chromatography analysis was carried out which showed that all of the starting material had reacted and the reaction mixture was quenched in dilute hydrochloric acid (water (51) plus 12.5M acid (50 cm3). The solid formed was filtered and dried to give 5.2 g, 97%, of crude product which was recrystallized from a mixture of ethyl acetate (20 cm3) and cyclohexane (100 cm3) to give (iii) as a yellow solid in a yield of 2.7 g, 50%.

Connection 2

Compound (iii) (2.6 g, 3.2 mmol) was suspended in dry ethyl acetate (25 cm³) and solid carbonyldi-(1-phenyl-5-thiotetrazole) (1.86 g, 4.9 mmol) was added portionwise over a period of 5 minutes. A clear solution was formed which was stirred at room temperature for 1 hour. The solution was then diluted with ethyl acetate (75 cm³) and the whole was washed sequentially. with portions (100 cm3) of 3M sodium carbonate solution (3·), water and 3M hydrochloric acid (3·). The solution was then dried over magnesium sulfate and concentrated to give a glass (2.7 g).

This was taken up in pyridine (50 cm3) and water (25 cm3) was added. The mixture was heated to reflux for 10 minutes, then allowed to cool slowly and poured into brine (2 L). The solid product which separated was filtered off and dried to give 2.4 g, 74% of compound 2. Purification by column chromatography using toluene-ethyl acetate mixtures (1-9 to 1-4) as eluant, followed by recrystallization from ethyl acetate/petroleum ether (60-800) afforded the product (2) as a white solid, mp=64°, hplc (observed at 275 nm)=99%.

C₄�9;H₆₁ClN₈O₄S₂

calculated: C 58.5; H 6.1; Cl 3.5; N 11.2; S 6.4%;

found: C 58.7; H 6.2; Cl 3.7; N 10.9; S 6.1%.

Positive ion FAB mass spectrometry showed (MH)+ at 1005 m/z. The 1H NMR spectrum in CDCl3 was consistent with the desired structure and showed approximately 30% enolization.

Reference compound H was prepared as a solid as described above, mp=65º, HPLC (detected at 275 nm)=93% with 7% impurities or enolized coupler.

C₄�9;H₆₁ClN₈O₄S₂

calculated: C 58.5; H 6.1; Cl 3.5; N 11.2; S 6.4%;

found: C 58.5; H 6.2; Cl 3.5; N 10.9; S 6.6%.

Positive ion FAB mass spectrometry showed (MH)+ at 1005 m/z. The 1H NMR spectrum in CDCl3 was consistent with the desired structure.

Example 2

The properties of coupler (2) of Example 1 were compared with those of coupler A and coupler H. Coupler A had the formula:

Each DIAR coupler was coated in a 2-layer Causer-Receiver format on a photographic film support over a gelatin layer containing gray colloidal silver as an antihalation layer with a protective overcoat of 5.4 g/m² gelatin as follows (coating weights are given in g/m², emulsion coating weights are given as g/m² silver):

Gelatin 2.7

yellow coupler B 1.2 (causer layer)

DIAR couplers (various)

green-sensitized silver bromoiodide emulsion 1.6

Gelatin 0.9

2,5-bis(1-methylundecyl)- 1,4-benzenediol 0.1

Gelatin 2.4

Coupler C 0.7 (receiving layer)

red-sensitized silver bromoiodide emulsion 2.6

carrier

The couplers used corresponded to the following structure: Matchmaker

The DIAR couplers were applied at different coating thicknesses and their effectiveness was compared with control pivaloylacetanilide couplers.

The coatings were exposed in an EASTMAN 1B sensitometer through a 1 cm wide, 31-step (0.4 log E) neutral density step wedge through a Wratten filter 99 to expose the causer layer and in a superimposed 0.5 cm wide step wedge through a Wratten filter 12 to expose the causer and receiver layers.

The exposed coatings were developed in the C41 developing baths described in the British Journal of Photography Annual 1977, pages 204-5, at a temperature of 38ºC and using a development time of 3.25 minutes. The contrast of the causer and receiver layer images was measured and the percentage contrast reduction was calculated using the following formula:

Go-Gx/Go · 100

where Go is the contrast without any DIAR coupler, and Gx is the contrast in the presence of the DIAR coupler in the amount given in Table 2. Table 2 Coupler No. Causer contrast Receiver contrast % Causer reduction % Receiver reduction (state of the art)

From the data obtained, it is apparent that superior contrast reduction percentages were achieved for each coating of Coupler 2 of the invention as compared to those achieved for Comparative Couplers A and H.

Sharpness measurements were made using coatings that matched the causer contrasts. The coatings were subjected to neutral exposure through a Wratten filter 12 to expose both the causer and the receiver. Sharpness was determined by calculating the CMT acutance values and the AMT acutance values. The application of CMT is described by RG Gendron in a paper entitled "An Improved Objective Method for Rating Picture Sharpness: CMT Acutance", published in the Journal of the SMPTE, 82, 1009-12, 1973, where CMT is defined as follows:

CMT = 100 + B log (area of cascaded MTF)/(area of eye MTF)

where B = 42.

AMT is believed to more accurately represent the perceived sharpness in copies, which is why AMT was used as a measure of sharpness in the case of 35 mm format. AMT is defined by the same formula as CMT, except that B = 66.

Consequently, coatings containing 11.3 x 10-5 mol/m2 of Coupler 2 with a Causer contrast = 1.28 and 16.9 x 10-5 mol/m2 of Coupler A with a Causer contrast of 1.32 were used for the sharpness measurements.

Results: Coupler 35 mm system AMT

A change in CMT or AMT value of greater than one unit is considered to indicate that a perceptual change in sharpness has occurred. On this basis, Coupler A and Coupler 2 show equivalent behavior when Coupler 2 is applied at only 2/3 the coating thickness of Coupler A. This means that Coupler 2 has a reactivity advantage over the prior art Coupler A.

Example 3 Coupler 2 in a purple dye-producing layer

A photographic material was prepared as described in Example 2 with the following exceptions:

Causer - Coupler B was replaced by the magenta coupler D (see below) in a coating thickness of 0.77 g/m²

Receiver coupler C was replaced by the yellow coupler E (see below) in a concentration of 1.3 g/m². The comparison coupler was the DIR coupler F (see below).

Comparing the effects of the inhibitors released by a DIR and a DIAR coupler is difficult because the timing change results in longer range effects. These longer range effects result in stronger interframe effects and sharpness boosts, especially in the case of the larger formats. For this reason, DIARs are preferable to DIRs in many applications.

Contrast data: %r Red of the total without coupler F Coupler 2

In cases where contrast was increased, negative values are given for %Gr red receiver.

The % receiver reduction of the total percentage reduction is given by the equation:

%Gr/%Gc + %Gr

and is indicated as zero if negative values occurred.

In the case of the 10.7 x 10-5 moles/m2 concentration of coupler F and coupler 2, the causer contrasts were very well matched (0.61 versus 0.58). Here, coupler 2 showed a larger receiver contrast reduction of 48% versus 32% in the case of coupler F. This means that coupler 2 and coupler F can be considered as having approximately the same activity in the causer, but with coupler 2 having an advantage in the receiver.

Sharpness data of these two coatings were as follows: 35 mm System AMT Profit

These data show that the Coupler 2 has a noticeable sharpness improvement in the case of the 16mm format, However, it has a more pronounced advantage in the case of the larger 35mm format, in which case the timed release of the inhibitor from the DIAR coupler becomes more important.

Structures: Matchmaker

Claims (8)

1. Non-diffusing photographic color coupler of the general formula: where TIME stands for a group of formulas: and in which: R is an alkyl group, R and R each are hydrogen or an electron-withdrawing group of the formulas: -SO₂-NH-R�sup6; -NO2; -SO-R6 -CN -SO₂-R⁶-CF₃ -CO-R&sup6; -OP(OR6)2 -CO₂R⁶ or -OSO₂R⁶ where at least one of the radicals does not consist of hydrogen, R4 is hydrogen or one or more substituents, R⁵ is an alkyl group having 1 to 4 carbon atoms or a hydroxyphenyl group, R6 is an alkyl group, R⁷ is one of the following groups -NO₂, -NHSO₂CH₃, -NHCOCH₃, -SO₂NHCH₃, -SO₂CH₃ or -CN, R⁶ is hydrogen, chlorine or a methyl group, R⁹ is hydrogen or R⁹, PUG a residue of a photographically usable compound and n is 0 or 1. 2. A coupler according to claim 1, wherein R6 represents an alkyl group having 1 to 20 carbon atoms. 3. A coupler according to claim 1 or 2, wherein PUG represents the residue of a development inhibitor or the residue of a development accelerator. 4. A coupler according to claim 3, wherein PUG is the residue of 5-mercaptotetrazole. 5. A coupler according to claim 1 having the following formula: wherein R¹⁰ represents an alkyl group having 1 to 20 e atoms and R¹¹ represents an alkyl or aryl group. 6. Photographic coupler with the following formula: 7. Photographic photosensitive material with a support on which at least one silver halide emulsion layer is applied, to which a coupler according to one of claims 1 to 6 is assigned. 8. Multi-colour photographic photosensitive material according to claim 7 with a support to which is applied a yellow dye image-forming unit with at least one blue-sensitive silver halide emulsion layer to which is assigned at least one yellow dye-forming coupler, and magenta and cyan dye image-forming units with at least one green- or red-sensitive silver halide emulsion layer to which is assigned at least one magenta or cyan dye-forming coupler, wherein at least one emulsion layer is assigned a coupler according to one of claims 1 to 6.